Paper and method of making



Feb. 2, 1937. N R 2,069,648

PAPER AND METHOD OF'MAKING Filed Feb. 10, 1936 INVENTOR. .Pefer I? Dz/mer I ATTORNEY5 Patented Feb. 2, 1937 UNITED STATES PAPER AND METHOD OF MAKING Peter F. Denner, Kalamazoo, Mich., asslgnor to Kalamazoo Paper Company, Kalamazoo,

Mich.

Application February 10, 1936, Serial No. 63,182

I 9 Claims. (01. 91-38) The main objects of this invention are:

v First, to provide a sheet of paper having an in tegral reflecting surface, the sheet being well adapted for use as a wrapper, for heat insulation and the like.

Second, to provide a grease and moisture proof paper well adapted as a wrapper for foods and the like and which may be economically produced.

Third, to provide a method of making paper of the foregoing character, which is simple and economical in practice and results in a sheet of very desirable appearance and insulating properties.

Objects relating to details and economies of my invention will appear from the description to follow. The invention is defined and pointed out in the claims.

A structure which is a preferred embodiment of my invention is illustrated in the accompanying drawing, in which:

Fig. 1 is a diagrammatic view in side. elevation of a coating machine adapted to apply various coatings to a web of paper during the practice of my method.

Fig. 2 is a diagrammatic view in side elevation of a calendering machine acting to polish the coating of oxidized metal broken down.

Fig. 3 is a similar view of a machine in which a moisture and grease repellent coating is applied to the reflecting surface, the web being subsequently desiccated.

Fig. 4 is an exaggerated fragmentary perspective view of a sheet of paper embodying features of my invention, the steps being illustrated in the form of layers for clearness.

Referring to the drawing, l is a web of paper which passes from the supply roll 2 through the coating machine 3 and to the roll 4. As the web travels under the drum 5, the rotating brush 6 applies a base coating 1 to one side thereof, the brush being supplied with the coating mixture 8 by the roller 9. The base coating is subsequently distributed over the surface of the traveling web I by the brushes it. Before the coated web is wound on the roll 4, the web is passed through drying loops II or other suitable drier wherein the coating is dried sufficiently to prevent sticking between the convolutions of the web on the roll 4. This coating may be of any desired color.

After the web has been coated on one side in the foregoing manner, it is passed through a coating machine similar to that illustrated in Fig. 1, wherein a base coating I3 is applied to the other side of the Web in a similar manner, the material passing from the supply roll 2 through the machine to the roll 4. Since the same or a similar machine is employed in imparting three coatings to the web, it has been illustrated only once in Fig. 1, web I being understood to have one, two, or three coatings applied thereto as the case may be. .The base coating preferably comprises a mixture of clay, casein and wax in the proportion by weight of 100 parts of clay to 16 parts of casein to 10 parts of wax. The'base coating 1 may, as stated, contain a pigment to color one side of the sheet, but the base coating [3 on the other side of the sheet is preferably white.

After the base coatings have been applied to both sides of the web, the latter is passed through another coating machine similar to that illustrated in Fig. 1, wherein a coating of a broken down metal oxide is applied to the base coating I3. In this case, the web likewise passes through the machine from the supply-roll 2 to roll 4. The coating which I prefer to use comprises a mixture of oxide of zinc or tin which has beenbroken down, casein and carnauba wax in the proportion by weight of 100 parts of broken downmetal oxide to 16 parts of casein to 10 parts of Wax. I preferably employ the product of the breaking down of an oxide of tin in this second coating since when polished it gives a brilliant finish.'

The product of the breaking down of zinc oxide may be used, but this gives a rather leadened finish. I have found that a product marketed under the trade name Argentine is suitably employed in the above described coating to follow the base coating; The substance to be combined with casein and wax, which I have termed an oxidized metal broken down, may be produced by treating the oxide with muriatic acid, the product rising to the surface and having the appearance of a froth. I have also found colloidal tin to be very satisfactory for my purpose.

Such a coating will resist salt and is resistant to chemicals, whereas aluminum and aluminum coated articles are deteriorated by salt and are not particularly resistant to chemicals.

The above described secondary coating has a dull and dark appearance and in this condition acts as a heat absorber rather than as -a heat insulator. To secure the polished effect which I desire, the paper is next passed through a calendering or polishing machine l1, Fig. 2, wherein} the web in passing from the supply roll, indicated in machine l1 by the reference numeral IE, to the roll I8 is subjected to the differential movement of a fast polishing roll l9 and a slow polishing roll 20, the latter being driven by the roll 2|. As the coating comprising metal oxide broken down passes under the fast polishing roll l9, it is given a highly reflecting metallic appearing surface by the slip or friction polishing action of the roll. This highly reflecting surface has the appearance. of metal foil, is a good heat and light insulator and has a very attractive appearance.

In Fig. 4, the secondary coating is indicated being indicated at 23.

-' ner is next run through the pyroxylin coating machine 24, Fig. 3, and wound on the roll 25,

the web traversing the pyroxylin applying -appar'atus 26, the distributing apparatus 21 and the desiccating rolls 28. The coating of pyroxy-, lin or cellulose is applied to the polished surface 23 to provide a moisture and grease repellent coating 28, Fig. ,4. "The last coating is substantially transparent and increases the reflecting power of the metallic appearing surface and improves the appearance of thevproduct. If desired, the last coating may beg-omitted.

In the foregoing manner, I provide a sheet 30 having on one side a surface permitting printing and on the other side a surfacewhich has the appearance of being covered by metal foil or the like, providing a reflecting insulating surface, and also when coated with pyroxylin or cellulose a grease and moisture proof surface. My method is applicable to a paper web of any kind of stock such, for example, as that used in making containers, wrapping paper, building paper or the like, the stock in any case being given a continuous metallic appearing surface which greatly increases the insulating properties of the paper. The sheet may be used as an insulator either in protecting foods or for heat insulation or the like. In order to increase the may obviously be used. l

reflecting or heat insulating capacity of the sheet, it may be embossed to produce a multiplicity of angular projections on the metallized surface.

An important feature of my invention resides in the fact that it is not necessaryto add wax to the final coating of cellulose, as is. usually the case, inasmuch as sumcie'nt'wax constitutes a part of the base and secondary coating composition. I have stated that cellulose or pyroxylin are used as lacquers. However, other lacquers The subject matter of my invention flnds commercial application in wallboards, building paper and their manufacture, and in-other relations. Building paper is made up of two sheets,

of my product pasted on a jute sheet and is used in the walls of buildings, etc.

I have illustrated and described my improve-- 'ments. in an embodiment which I have found very practical. 'I have not attempted to illustrate or describe other embodiments or adaptations as it is believed this disclosure will enable those skilled in the art to embody orimprovements as may be desired.

Having thus described my invention, what I secure by Letters both sides of a web of paper with a base coating comprising a mixture of clay, casein and wax,

covering said base coating on one side with a coating comprising a mixture of an oxidiled covering said base coating on one side with a coating comprising a mixture of an oxidized metal broken down, casein and wax, polishing said second coating to provide'a highly reflecting surface, and covering said reflecting surface with a moisture and repellent coating.

3. The method of making paper of the char-- acter set forth, comprising the steps of covering both sides of a web of paper with a base-coating comprising a mixture of clay, casein and wax, covering said base coating on one side with a coating comprising a mixture of an oxidized metal broken down, casein and wax, and polishing said second coating to provide a fleeting surface.

4. A sheetof paper having a base coating comprising a mixture of clay, casein and wax,.a coating overlying said base coating comprising a mixture of an oxidized metal broken down, casein and wax, said second coating having a highly polished reflecting surface, and a moisture and grease repellent coating overlying said reflecting 5. A sheet of paper having a base comprising a mixture of clay, casein and wax, and a coating overlying said base coating comprising a mixture of an oxidized metal broken down, casein and wax, said second. coating having a highly oxide broken down, 16 parts casein, and 10 parts wax, and polishing said metallic coating.

7. The method of making paper of the characterset forth, comprising the steps of covering a side of a web of paper with a base coating'colnprising a mixture of clay, casein, and wax, covering said base coating witha metallic coating comprising a mixture of a metal oxide broken down,casein, and, wax, and polishing said metallic coating.

8. The method of acter set forth, comprising the steps of covering aside of a web of paper witha basecoating comprising a mixture of clay, casein, and wax,

.-= coating with-ametalliccoatha metal oxide broken down, and

polishing d metallic coating.

9. The method of making paper of the character set forth, comprising the steps of covering.

making paper of the'chab a side of a web of paper with a base coating oomprising a mixture of clay, casein, and wax, and covering said base coating with a metallic coating comprising a mixture of a metal oxide down, casein, and wax. 7

rm I. DINNER. 

